DE 103 33 989 A1 relates to a method for digital data transmission from a sensor to a control unit. Sensor values of a sensor are divided for data transmission at different resolutions. The sensor values form a first range of values having successive sensor values, in which the division of the first range of values for data transmission is carried out as a function of a variable relevant for the control unit. The variable is a second range of values of threshold values of a triggering algorithm for restraining means, the sensor values in the second range of values being transmitted from the sensor to the control unit at a higher resolution. The second range of values is in particular selected from the lower half of the first range of values.
DE 10 2004 001 293 A1 relates to an apparatus and method for data transmission with a reduced data volume. A method is proposed for sending multimedia data which is transmitted in time blocks, selection of at least one first time block being initially carried out as the basis for an extrapolation. Selection of at least one second time block of data which is to be estimated is then carried out, followed by sending the data in the at least one first time block and sending representative data for the extrapolation, which has a reduced data volume compared to the data which is to be estimated, during at least the second time block. DE 10 2004 001 293 A1 is also directed to a method for receiving multimedia data which is transmitted in time blocks, data initially being received in at least one first time block and representative data being received in at least one second time block. This is followed by the extrapolation of the data of the at least one second time block based on the data of the at least one first time block and the representative data.
Electronic control units are increasingly used today in the automotive sector in applications such as engine control units, ABS, airbag triggering systems, ESP, and the like. The development of a battery pack having an associated battery management system is required for vehicles which are equipped with an electric drive. A battery management system generally includes control units having software for monitoring the battery functionality. Depending on customer requirements or existing installation spaces, the topologies of battery packs vary widely with respect to the number of cells, modules, sensors, and so forth. Typical battery management systems ensure that cells and packs function safely and reliably. They monitor and control currents, voltages, temperatures, insulation resistances, and other variables for the cells and the entire battery pack. These variables make possible the implementation of the management functions which must be ensured by the battery management system, thus increasing the life span, reliability and safety of the battery system.
Battery management systems generally include a plurality of control units, on which individual software functions run. Depending on the number of cells, the number of sensors, and the distribution of the battery modules in various installation spaces in the automobile, a control unit topology results having a primary control unit and a plurality of subordinate sensor control units for detecting the measurement data directly at the individual battery modules. For example, the measurement data includes the voltages, temperatures, currents, and the like of the individual battery modules. The detected data is generally exchanged between the control units via a communication bus, for example, a CAN bus.
The use of a communication bus having a defined bandwidth limits the total data traffic which can be transported on the bus in a specified time interval. A low maximum bandwidth of the communication bus minimizes the probability of malfunctions caused, for example, by EMC irradiation. However, the use of a large number of battery modules and associated sensor control units makes it necessary to communicate all measurement data to the master control unit on the bus at a high frequency. The measurement frequency is therefore limited by the bandwidth of the communication bus and the number of battery modules.